Helmet



FIG. 1 is a perspective view of a helmet with the unclaimed strap portions omitted;

FIG. 2 is a front view thereof;

FIG. 3 is a top view thereof;

FIG. 4 is a right-side view thereof with portions of the unclaimed strap portions omitted, the left-side view being a mirror image of the right-side view;

FIG. 5 is a rear view thereof; and,

FIG. 6 is a bottom view thereof with the unclaimed strap portions omitted.

The straps shown in broken lines form no part of the claimed design. The dash-dot-dash lines in FIGS. 1, 2 and 6 depict a boundary between claimed and surfaces and form no part of the claimed design. 

CLAIM The ornamental design for a helmet, as shown and described. 